June 30, 2007

NOTHING'S RELATIVE:

A BASIC POINT ABOUT EINSTEIN'S life (1879-1955) is that he became more conservative when he reached middle age; not so much politically -- he remained a man of the left to the end -- but in his scientific outlook. This was reflected above all in his prolonged and unresolved dispute with Niels Bohr and Werner Heisenberg about quantum mechanics. If you are unfamiliar with that controversy, there could be no better introduction than Isaacson's. He covers it in about 40 lucid pages, encompassing the contributions of Erwin Schroedinger and others. Most of us know little more than that Heisenberg enunciated an uncertainty principle, wherein observation affects the thing observed; to which Einstein retorted that God does not play dice. Here you will learn, painlessly, a good deal more than that.

Heisenberg insisted that an electron does not have a definite position or path until we observe it. This was a feature of the universe, he claimed, not just some deficiency in our ability to measure. In denying that there is an objective reality out there, it undermined classical physics. When Einstein objected, Heisenberg confidently replied: "I believe that indeterminism, that is, the non-validity of rigorous causality, is necessary."

On the 200th anniversary of Newton's death, in 1927, Einstein defended classical mechanics. Two decades earlier he had "toppled many of the pillars of Newton's universe, including absolute space and time," Isaacson writes. Now he was a defender of Newton, of rigorous causality and (by implication) the established order.

Einstein: "You don't seriously believe that none but observable magnitudes must go into a physical theory?"

He was confronted with his own youthful rebelliousness.

Heisenberg: "Isn't that precisely what you have done with relativity?"

"Possibly," Einstein said, "but it is nonsense all the same."

Man is a subject, not an object.
Posted by Orrin Judd at June 30, 2007 11:33 PM